Abstract
Spheroids have emerged as a more reliable model for drug screening when compared with 2D culture models. Microfluidic based biochips have many advantages over other 3D cell culture models for drug testing on spheroids, including precise control of the cellular microenvironment. The control of the cell adhesion to the surface is one of the most important challenges affecting the size and the geometry of the spheroids which could be controlled by appropriate surface engineering methods. We have studied the modification of the PDMS surface properties treated by applying different concentrations of the two anti-fouling coatings (BSA and Pluronic F-68). The desired treatment of PDMS surface effectively inhibits cell adhesion to the surface and promotes cells self-aggregations to form more uniform and healthy spheroids for a longer period of time. The microscopic observations with qualitative and quantitate data revealed that surface properties drastically affect the number of the spheroids formed on-chip and their geometry. We used human breast cancer cell line (MDA-MB-231-GFP) while the concentration of the chemical coatings and incubation time were adjusted. Proper repellent PDMS surfaces were provided with minimum cell attachment and facilitated spheroid formation when compared with non-treated PDMS. The results demonstrate fundamental and helpful patterns for microfluidic based cell culture applications to improve the quantity and quality of spheroid formation on-chip which are strongly manipulated by surface properties (i.e., morphology, roughness, wettability and etc.)
Competing Interest Statement
The authors have declared no competing interest.
List of Acronyms
- AFM
- Atomic force microscopy
- BSA
- Bovine serum albumin
- EOF
- Electro osmotic flow
- HBSS
- Hank’s balanced salt solution
- PBS
- Phosphate buffered saline
- PDMS
- Poly dimethylsiloxane
- PEO
- Poly (ethylene oxide)
- Ra
- Average roughness
- SD
- Standard deviation
- SE
- Standard error
- SLA
- Stereolithography apparatus
- 3D
- 3 dimensions
- 2D
- 2 dimensions
- WCA
- Water contact angle